-- The ground seemed to shake in Napa on Saturday, which is another way of saying Raiders running back Michael Bush was rumbling downfield again.

Bush, notable in his absence through the early days of training camp, finally brought his 6-foot-1, 245-pound self to Wine Country. It was a welcome sight for coach Hue Jackson and the men in Silver and Black, especially with Darren McFadden out nursing a fractured orbital bone.

Bush participated in a handful of plays during the team's late-afternoon practice, after signing his one-year tender for $2.6 million. Bush had been a restricted free agent, but he fully expected to rejoin the Raiders all along - he knew other teams would not relinquish a first-round draft choice to sign him.

So there he went, taking handoffs and plowing ahead with the same lack of subtlety that carried him to 655 yards rushing last year, when he and McFadden formed a potent tandem. That's the plan again this season, though it must wait until McFadden returns from his injury.

Asked if McFadden's absence had any impact on his decision to sign the tender, Bush said, "Not really. I also got a strong bond with Rock (Cartwright) and Louis (Rankin). Those guys were taking a lot of reps. I kind of felt bad. I wanted to get here and kind of ease their pain a little bit."

Bush's absence had caused some ripples the past few days. On Thursday, he tweeted about watching Tiger Woods' return to the PGA Tour, prompting Raiders teammate Michael Huff to tweet in response, "Would somebody tell @michaelbush29 to bring his a- to Napa?"

Two days later, Bush complied. He looked "quick" and "lean," to borrow Jackson's ever-enthusiastic words, and that bodes well for a Raiders offense counting on No. 29 to churn out yards on the ground.

"Michael means a lot to this team," Jackson said. "You can't do it with one guy (at running back), and he's a very physical player. I think there are a lot of safeties across our division and our league who don't like running into him."

Bush's arrival did not count as the only earth-shaking event Saturday. Equally momentous was linebacker Rolando McClain planting himself in front of a semicircle of notepads and cameras.

McClain rarely speaks to the media - only two or three times as a rookie last season, not at all in the first week-plus of this camp - but he patiently fielded questions for seven minutes. The most interesting nugget: He lost 5 or 6 pounds this offseason and is playing "faster" than before.

Some of that, McClain suggested, traces to new defensive coordinator Chuck Bresnahan.

"Coach Chuck has made things a lot more defined, so I'm able to play a lot faster," McClain said. "So are the rest of the guys. We just believe in each other. I think guys are a lot more confident this year."

Saturday's practice also marked the first appearance in a Raiders uniform for tight end Kevin Boss. He signed a four-year, $16 million contract Friday, a tidy consolation prize after Zach Miller bolted for Seattle.

One unmistakable impression: Boss is one tall dude. He's listed at 6 feet 6, but he seems capable of reaching his arms halfway to the sky.

Briefly: The Raiders signed three wide receivers - Chad Jackson, Derek Hagan and Shawn Bayes - to cover a position racked by injuries. Hagan, a five-year veteran who has spent time with the Dolphins and Giants, played at Arizona State. ... Rookie wideout Denarius Moore made a nice play during practice, adjusting to catch a long pass from Kyle Boller.